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arXiv · 2308.03145

Cosmological scenarios from topological invariants: Inflation and Quintom theory with Barbero-Immirzi scalar field

Pollari Giacomo
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Abstract

In the present work we provide a cosmological description of the Palatini action with the addition of three well-known topological invariants, each of which is attached to a scalar field. As a consequence, torsion plays a central role, yielding an effective action with three dynamical scalar fields coupled to gravity subjected to the influence of a potential. A special heed will be addressed to inflation scenarios and quintom theory, although other noteworthy cases will be analyzed. Two out of three scalars can be thought as the Barbero-Immirzi scalar field coupled to the Holst and Nieh-Yan terms with a potential whereby they shape the evolution of the universe. The other field turns out to be a phantom that we couple to the inflaton that at late times holds the stage inducing a fast expansion

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Pollari Giacomo. 2023-08-06. Cosmological scenarios from topological invariants: Inflation and Quintom theory with Barbero-Immirzi scalar field. https://arxiv.org/abs/2308.03145

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